蝎毒多肽提取物联合化疗抑制Lewis肺癌血管生成实验研究

Effect of polypeptide extract from scorpion venom(PESV) with chemotherapy inhibited angiogenesis of lewis lung carcinomas

目的:观察蝎毒多肽提取物(polypeptide extract from scorpion venom,PESV)对Lewis肺癌荷瘤小鼠肿瘤血管生成的抑制作用并探讨可能的机制。方法:54只C57BL/6J小鼠皮下接种小鼠肺癌Lewis细胞,7 d后随机分为荷瘤对照组、化疗组和PESV组。以环磷酰胺对荷瘤小鼠进行化疗建立肿瘤化疗模型。按不同用药方法对3组小鼠进行干预,隔日测量肿瘤体积。各组每7 d处死6只小鼠,实验共进行28 d。以免疫组织化学方法检测各组肿瘤组织Ⅷ因子,α-SMA,Dll4及Notch1蛋白表达水平。以Ⅷ因子标记微血管,计算微血管密度(MVD),以α-SMA标记成熟有功能的血管,计算血管成熟度。以RT-PCR方法检测肿瘤组织Dll4,Notch1基因水平表达。结果:PESV抑瘤率为42.21%。PESV组肿瘤体积与化疗组存在明显差异(P<0.05),与荷瘤对照组有显著差异(P<0.01)。PESV组Ⅷ因子表达水平显著低于化疗组(P<0.05)。化疗组肿瘤组织α-SMA表达低于荷瘤对照组(P<0.01),PESV组显著低于化疗组(P<0.01)。化疗组Dll4及Notch1第28天表达低于荷瘤对照组(P<0.05),PESV组肿瘤Dll4及Notch1第21天表达显著低于化疗组(P<0.05)。结论:PESV可对Lewis肿瘤血管生成起抑制作用,其机制可能与抑制肿瘤微环境中血管生成相关因子Dll4及Notch1有关。

Objective： To study the effects of polypeptide extract from scorpion venom（PESV） alliance with chemotherapy on angiogenesis of Lewis lung carcinomas（LLC） and its mechanism.Method： LLC cells suspension（4×106 cells/mL） were subcataneously injected into 54 C57BL/6J mice in right armpits.Then the tumor-bearing mice were randomly divided into three groups： the control group,the chemotherapy group and the PESV group.Cyclophosphamide was used to establish the model of cancer.Chemotherapy and PESV were added to the PESV group.Every 7 days,6 mice of each group were executed,and the experiments were carried out for 28 days.The tumor volume and inhibitory rate were determined.Immunohistochemistry and RT-PCR were used to determine the expression of factor Ⅷ,α-SMA,Dll4 and Notch1 in tumor tissue.Correlation analysis was used to identify the relationship of factor Ⅷ and calculate microvessel density（MVD）,α-SMA and vascular maturity.Result： The inhibitory rate of PESV was 42.21%.Comparing with the chemotherapy group,the expression of tumor factor Dll4 and Notch1 in the PESV group were decreased significantly（P0.05）.The expression of factor Ⅷ and а-SMA in the che group is lower than the control group（P0.05）,while it′s higher when compared with the PESV group（P0.01）.Expression of Dll4 and Notch1 in the chemotherapy group at the 28th day were higher than the control group（P0.05）,and the expression in the PESV group at the 21st day were significantly lower than the chemotherapy group（P0.05）.Conclusion： PESV could inhibit the angiogenesis of LLC.It might be attained by decreasing the level of angiogenic factors,that are factor Ⅷ,α-SMA,Dll4 and Notch1 in tumor microenvironment.